CARL SAGAN and FRANK DRAKE are professors of astronomy at Cornell University, where Sagan is director of the Laboratory for Planetary Studies and Drake is director of the National Astronomy and Ionospheric Center. "In returning from the International Astronomical Union meetings in Sydney in 1973," they write, "we spent some days skin-diving in Bora Bora in Tahiti, where our Scientific American article was first devised. Since Polynesia had been settled by voyagers crossing thousands of kilometers of ocean, we thought a two-kilometer journey by outrigger canoe would be a modest homage to those intrepid explorers, particularly since we were assured that such canoes are unsinkable. We discovered that this is true; when they are swamped, they only sink as far as the shoulders of the passenger, and the outrigger affords some discouragement to those sharks that are to starboard. The experience confirmed our belief that radio communication is easier than direct contact."
The Search for Extraterrestrial Intelligence
There can be little doubt that civilizations more advanced than the earth's exist elsewhere in the universe. The probabilities involved in locating one of them call for a substantial effort.